Parent Company Only Condensed Financial Information - CONDENSED STATEMENTS OF CASH FLOWS (Details) - USD ($) $ in Thousands	12 Months Ended			24 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 8,734	$ 3,644	$ 2,822	$ 2,822
Adjustments:
Stock compensation expense	1,503	554	388
Change in other assets	(3,351)	(2,309)	(202)
Net cash provided by (used in) operating activities	9,428	3,979	6,319
Cash flows from investing activities
Net change in loans	(119,609)	(71,086)	(54,461)
Purchase of equity investment without readily determinable fair value	(2,410)
Net cash used in investing activities	(142,059)	(108,791)	(65,572)
Cash flows from financing activities:
Exercise of stock options	378	942
Proceeds from the issuance of common stock		26,341	1
Net cash from financing activities	120,116	104,896	69,092
Net change in cash and cash equivalents	(12,515)	84	9,839
Cash and cash equivalents at beginning of the period	43,077	42,993	33,154
Cash and cash equivalents at end of the period	30,562	43,077	42,993	42,993
Esquire Financial Holdings Inc
Cash flows from operating activities:
Net income	8,734	3,644	2,822
Adjustments:
Stock compensation expense	1,503	554	388
Equity in undistributed subsidiary income	(10,278)	(4,139)	(3,143)
Change in other assets	(563)	(388)	(199)
Change in other liabilities	(9)	34	(105)
Net cash provided by (used in) operating activities	(613)	(295)	(237)
Cash flows from investing activities
Investments in subsidiaries	(11,000)	(12,000)	(4,000)
Net change in loans	(1,775)
Purchase of equity investment without readily determinable fair value	(2,410)
Other assets	0	0	1,250
Net cash used in investing activities	(15,185)	(12,000)	(2,750)
Cash flows from financing activities:
Exercise of stock options	378	942	0
Proceeds from the issuance of common stock		26,341	1
Net cash from financing activities	378	27,283	1
Net change in cash and cash equivalents	(15,420)	14,988	(2,986)
Cash and cash equivalents at beginning of the period	19,461	4,473	7,459
Cash and cash equivalents at end of the period	$ 4,041	$ 19,461	$ 4,473	$ 4,473